PowerTec Lifter Tec pt 2

yes the subject zinc zinc is probably one of the most touted additives ever in automotive history and it's won a reputation which it may have deserved 50 years ago but not anymore let me let me fill you in first this product is always referred to as just zinc or z ddp so what exactly is that what we are really talking about here is a group of compounds which falls into the zinc diacyl dithiophosphate group there's actually three sorts of this and they're activated at different temperatures a good place to find out more about this zinc additive is to go to the uh joe gibbs oil website um there's a link going across the bottom here and my friend lakespeed jr gives a pretty good description of what's going on with this chemical it's quite complicated but the truth of the matter is it's way out of date there are better things out there let me detail those now so what might be better than our zinc additive oh let me make a point here more zinc in the oil does not mean more protection there comes a time when if you have too much zinc in an oil it will cause things like the lifters to craze like crazy paving on a pathway and there's a loss of power and things like this so zinc the amount of zinc you put in the oil has to strike a fine balance and it's different for every oil there's some oils that are very well blended you put zinc in even a small amount you've now degraded your oil on the other hand there's cheap oils which don't have any zinc you put some zinc into that and sure enough they get better but do you know how much to put in no let's talk about another additive that's replaced or can replace zinc but i have to make a disclaimer here way back some 25 years ago i was approached to test an additive called oil extreme and it was a startup company and of course it's pretty expensive to hire me for a time uh to do a test on an oil it might look like you just throw it in and check it ah that worked no i had to build an engine especially for the testing and it had to be a loose engine i.e it's one which absolutely would benefit the least from an oil improvement in other words it had all the clearances just right for the minimum amount of friction and uh at that it made the most power basically it was a two barrel uh um circle track engine it would it had winning power capability as well anyway we put a four barrel carb on it to make testing easier and i tested the lubricant right i did a bunch of tests this way and that and the oil came out just like the guy who wanted it tested claimed it would now here's the interesting thing you won't believe how many people have come to me the oil salesman and said look i've got the oil additive you need to test this it'll make your career right why are they coming to me i've already got a career that's made in journalism right i don't need anything i said and i said well i've got to charge you no no no you don't understand you need to test this it'll do it wonderful things for your reputation and i said i don't need any more reputation right if you want this tested you pay for it if you're so sure it's going to work paying for it shouldn't be in a a problem anyway this guy came in to me with oil extreme and wanted it tested and i told him i said it's gonna cost and he said well okay how much and i said well i need a deposit of twelve thousand dollars and it could be a little bit more after that okay and he got his checkout and he wrote me a check for twelve thousand dollars why because he knew that if i tested it properly it was going to work just like he said well it did anyway the point is this it was a startup company and funds were tight that 12 000 he used to pay the deposit was not far off what was in the bank so i could see that what was going to happen is by the time he'd gone through and tried advertising this and not that and everything else the company was going to go bankrupt and you as a potential end user would lose a very good oil additive that is at least twice as good as zddp so i invested in the company in today's money it's well over twenty five thousand dollars now i have to point out to you that those people those big automotive celebrity people who advertise additives on tv we don't have to go into names you know who they are they're paid to do that they don't even test the stuff well probably don't and if they do they don't tell you the truth now ask yourself this why would i spend all that money to invest in a product which didn't work just as i'm going to tell you it works works damn fine there we go that's all you need to know now how do you get this just go to the oil extreme website and order it right it's not cheap but nothing ever is that's good okay next thing on the agenda adjusting the lash now i say the lash here because it seems like a fairly inconsequential thing but it can have a great difference not quite as much as one hot rod story that i read many many years ago that was obviously a paid for deal the guy must have been bribed or stupid one of the two right and this was about a dial indicator device for setting the lash on a solid tappet cam well they got on the chassis dyno with a corvette and adjusted by hand versus suggested by the lash adjuster which could adjust the lash to probably better than a thousandths if you took care of it was 60 horsepower at the wheels and i thought wow i have got to make one of these for my racing mini so i did got to the chassis uh test facility chassis dino test facility a few days after i'd made up this device and adjusted my valve train as accurate as i could with feeler gauges then dynoed it next i adjusted the lash with the lash adjuster to get it just right now if i was surprised i could be up to two or three thousandths out with the feelers so it was different uh a different but but you know i've adjusted valves a lot now i did this test 50 years ago yeah it's a long time 50 years ago anyway re-ran the dyno test and guess what we couldn't even see a whole horsepower difference and i came to the conclusion that everything you read in magazines may not be true unless i wrote it well that's not quite accurate right i know that there's some writers out there and i i can name them who are very trustworthy with their results and they do their testing very thoroughly but there's also a lot of rip-off artists and maybe that's a video a tell-all video in itself right these rip-off artists have cost me a great deal of money if i set a quarter of a million dollars i would be probably very well on the conservative side but anyway lash enough of these stories valvelash let's first deal with solid lifters right there is this tendency amongst many hot rodders and usually the newer ones that think that if they adjust the valve lash tighter then they've got more duration so it should make more horsepower well the unfortunate thing is is that the lift rate is so low on the tap it ramps that it constitutes nothing more than a leak in the system and usually the power drops we find that opening the seat valves off their seats fast and closing them fast helps the power output by virtue of the fact of closing the valves slightly earlier and quicker into usually at the end of the cycle and this bumps up torque now the best deal is is to have the exhaust a little looser than the intake and that's not because of the expansion that is because the exhaust is much more uh influential on the idle quality and the vacuum may not make much difference on a race motor but that slight delay between intake and exhaust can make a difference in horsepower i usually start off with the lash this is on the dyno i usually start off with the lash a little on the loose side and then progressively tighten up first the intake and then the exhaust and then i go back to the intake um figure that you're going to probably end up with two or three thousands more lash than you anticipated now you can't use too much clearance because it will beat the valve train to death also having that very fast closing on the intake can lead to early valve bounce and it'll hammer the seats out so be moderate there now let's turn our attention to the hydraulic cams the standard method here is to adjust the uh the lash down until the push rod just starts to bind up when you try twisting it and then turn it a quarter turn more what's the reason for this well if you ask most hot rodders uh and for a precise reason they don't have one well that's what the manufacturers recommend well they do but not for any performance reasons other than the fact that a quarter turn into the system will mean that the chances of adjusting the lifters in the next hundred thousand miles assuming the oil's changed is pretty close to zero so it's a convenience deal i.e you adjust the lifters and you forget them uh now then are we performance enthusiasts or not yes we are why the quarter turn in well like i said it's just for convenience if you've got a lifter that is bleeding down and most of them do to a certain extent or other then what happens is the lifter will bleed down and the chamber in the lifter will have to refill almost in its entirety before the next cycle comes about so the bleed down causes a reduction in duration and also it's on the end of the stroke that's most important that's if we've got headers on we're going to have that extraction effect we want that exhaust to or intake to be available or give lift at a time when the scavenge cycle wants it so how can we avoid that well it's quite simple instead of adjusting it quarter of a turn down from the top how about doing it a quarter of a turn up from the bottom what does this what's the advantage of this well first off it's very inconvenient adjusting it you have to empty all the lifters first secondly um on the advantage side we find that the lifter can only bleed down or collapse a short distance before it bottoms out so that means we have full lift and pretty much most of the duration the second reason is that it takes very little oil to be pumped into that lifter to fill it up ready for the next cycle so the propensity for it to misbehave is vastly reduced when i say vastly i mean we can go from what may will represent a hundred percent problem right of collapse and by adjusting it towards the bottom we can reduce that hundred percent problem down to five percent so makes a difference now somebody's gonna say what about pump up well remember we already went through that the pump up is due to the spring not the lifter right there is one snag when you well i say one snag there is a snag you need to take care of when you adjust the lifters down this far you must check that the oil comes through the system and comes out of the rockers sometimes the lifters don't have the oiling system functional right at the bottom of their travel now let's look at the limited travel hydraulic lifters essentially they are lifters which are made so that there's very very short amount of travel and and they emulate right out the gate what happens when you adjust the lifter all the way down right so uh that's an area you need to take care of now how much difference can there be in horsepower well that's a good one let's take a big block with its need for a high lift in the first place it's 1.7 rocker trying to give it a high lift in the second place and a lot of spring on there to keep the valve train uh under control we can find that adjusting out the lifter so that bottoms out rather than a quarter turn in can be as much as 15 to 20 horsepower so we're not talking about an inconsequential amount of course there's going to be somebody who's got a great set of lifters in there they they dyno it then they adjust them to the bottom and it makes almost no difference well the fact of the matter is you must have tight lifters and that's good last point on this subject what about those fast bleed down lifters that are supposed to uh give you more vacuum at idle and and then as the rpm goes up so they stay pumped up longer and come back up to full duration well the bottom line is is they never get fully pumped up again they never get to the point where they are acting as a true tight hydraulic lifter they are always bleeding down sure you get more vacuum but you could have got that by putting in a cam and some stiff hydraulic lifters the cam would have to be shorter it would make more torque it would run quieter and it would make more power at the top end so long as it was chosen correctly one of the problems with just doing a quick change of lifters to see what power difference can be had from these fast bleed down lifters is that it completely alters the timing of the cam the bleed down happens on the closing side so what you effectively do is to it advances the timing of the camp all the way forward and cuts the area right so when you install that cam and time it even if the timing figures you were given were correct the lifters make it incorrect my advice is think twice before you use fast believe downlifters okay we've we've discussed a lot of aspects here but let's talk about lubrication in terms of how the lifters are oiled first off let's do the flat tapping stuff because that's the most critical i think the thing to note there is that uh some of the lifters have holes drilled in them and i've already mentioned that but one of the ways we need to look at things is in terms of how much oil gets onto the profile of a flat topic lifter and there's a way of doing this that is probably better than having a lifter hole and it works on [Applause] engines that are particularly susceptible to lifter wear big blocks are a prime example but let's take a look at a simple tool that comcam sells that will lubricate your lifters just right here's the device in question it's a lifter groover this tool here this is the diameter of the lifter bore this tool sticks out slightly you feed this in from the bottom of the block like this hook this tool in here from the top and pull the lifter up it grooves it right to the oiling hole that goes from the front to the back of the block now that lifter grooving tool that i've just showed you works on solid and hydraulic cams especially good for hydraulic cams because it's not practical to put an oil hole in the face of a hydraulic lifter because then you'll speed up the bleed down rate and the lifter may go into a collapse mode under heavy stresses let's now take some roller lifters as an example here normally roller lifters are subject to higher loads but when we get to really extreme loads the normal roller lifter can suffer from unreliability and it can actually cause the rollers to break up several things you need to consider here you need to get a roller lifter with as big a roller on it as possible to reduce side loads and that increases the opening area as well not much but it does and you need to look into putting as bigger lifter diameter as possible so that you can get that bigger roller now let's consider the situation with extreme valve spring loads and i'm talking 800 900 even a thousand pounds over the nose maybe more if it's a pro stalker what you have to do here is you have to get the very best lifters possible there is a trend to have plain bushings in the roller lifters personally i'm not convinced that they're that much better if any than a good roller lifter bearing right i've seen both types break under extreme conditions so just call your cam supplier here and ask them what they think you should use with the profile that you may get and that should be the best route to follow now hopefully i've gone through a lot of stuff here that will help you run um your valve train better oh there is one thing i want to mention here it's a myth that roller lifters can accelerate the valve faster than flat tap it after all they look such big square profiles but if you check out the lift rate it gets cut down by the fact that that cam that looks so brutishly rectangular is calmed down by the fact that it's running against a roller now if we're talking about going to the limit a flat tappet cam is capable of accelerating the valve train off the seat faster than a roller where it comes to its limitations is in the velocity of the lifter once the contact patch has hit the edge of the lifter or close to it that's it that's as much velocity is as will go into the rest of the valve train on the other hand a roller lifter is only limited in the velocity department by how much duration it has the acceleration of a roller lifter is limited by the side pressure that it experiences and about 28 degrees is about as much as a typical roller lifter will take all right sure the pro stalker guys go more than that but boy they are running expensive valve trains you may not want to go there if you do then you better do your research really well okay that's it for my lifter session here um any questions you put them down at the bottom here and i'll see if i can get to answer them as for whatever we're going to talk about now we'll deal with that in the next video and so for now i'm going to say i'll see you next time and we'll be busy between now and then preparing our next tech video for you thank you for watching

Channel: David Vizard Performance

Views: 4,184

Rating: 4.9670782 out of 5

Keywords: Wondershare Filmora9

Id: edgwqzhS8BA

Length: 26min 15sec (1575 seconds)

Published: Sat Dec 19 2020